The invention generally relates to facsimile transmissions and, more particularly, the invention relates to establishing a facsimile transmission across a packet based network.
As known in the art, facsimile data commonly is transmitted across a public switched telephone network from a sending facsimile machine (xe2x80x9csending faxxe2x80x9d) that transmits the facsimile data, to a receiving facsimile machine (xe2x80x9creceiving faxxe2x80x9d) that receives the facsimile data. Various facsimile protocols thus have been deployed to specify the various facets for a facsimile transmission across such a network. For example, the V.34 protocol is one of a family of related facsimile and modem protocols that may be used to specify establishment, maintenance, and termination of a facsimile connection.
The V.34 protocol borrows processes from the well known V.8 protocol to establish a facsimile connection between a sending fax and a receiving fax. Specifically, when the receiving fax answers a call from the sending fax, the V.8 protocol requires that the receiving fax initially transmit of an xe2x80x9canswer tone messagexe2x80x9d (often referred to as xe2x80x9cANSAM tonexe2x80x9d) to the sending fax for a predefined amount of time. During this time, the receiving fax accumulates parameters that are common between the two fax machines for effectively transmitting and/or receiving the facsimile data. Once accumulated, the receiving fax adds the common parameters to a xe2x80x9cjoint menuxe2x80x9d message (often referred to as a xe2x80x9cJM messagexe2x80x9d), which subsequently is transmitted to the sending fax. Upon receipt, the sending fax uses the parameters in the JM message to transmit the facsimile data to the receiving fax.
Undesirably, various modem and facsimile protocols specify that various messages must be received by one of the two fax machines before the end of the ANSAM tone. For example, various modem and facsimile protocols require that the JM message must be received by the sending fax before the end of the predefined amount of time that the ANSAM tone is received by the sending fax (e.g., between about four to six seconds). Accordingly, problems arise when utilizing the V.34 protocol to transmit facsimile data across a packet based network (e.g., the Internet). In particular, the added delay of the packet based network can delay the transmission of the JM message from the receiving fax to the sending fax. Consequently, the sending fax may not receive a complete JM message before the end of the predefined amount of time that it is receiving the ANSAM tone. This can cause various problems that can degrade and/or terminate the connection between the sending fax and the receiving fax.
In accordance with one aspect of the invention, if a given joint menu message is not received by the end of receipt of an answer tone message, then an alias joint menu message is forwarded to a sending facsimile machine until the given joint menu message is generated and forwarded to the sending facsimile machine. To that end, a method and apparatus for establishing communication between a sending facsimile machine and a receiving facsimile machine first receives an answer tone message for a specified time. It then is determined if a given joint menu message has been received from the receiving facsimile machine at any time during the specified time. If it is determined that the given joint menu message has not been received from the receiving facsimile machine at any time during the specified time, then the above noted alias joint menu message is forwarded to the sending facsimile machine. The alias joint menu message is different from the given joint menu message and thus, not a true joint menu message that can be used by the sending facsimile machine.
In illustrative embodiments, the given joint menu message is received and forwarded to the sending facsimile machine after the given joint menu message is received. After the given joint menu message is received, the forwarding of the alias joint menu message may be terminated. The answer tone message may comply with various facsimile protocols, such as the V.X family of facsimile protocols. The answer tone message may be received from any type of network, such as a packet based network. The alias joint menu message may be repeatedly forwarded to the sending facsimile machine by a network device until the given joint menu message is received by the network device. In illustrative embodiments, the alias joint menu message indicates that the given joint menu message is forthcoming.
In accordance with other aspects of the invention, a method and apparatus of establishing facsimile communication between a first facsimile machine and a second facsimile machine receives an answer tone message for a specified time. In illustrative embodiments, the answer tone message is received over an initial facsimile connection between the first facsimile machine and the second facsimile machine. It is then determined if a given message has been received from the first facsimile machine at any time during the specified time. An alias given message is forwarded to the second facsimile machine if it is determined that the given message has not been received from the first facsimile machine at any time during the specified time. In illustrative embodiments, the alias given message has data that maintains the initial facsimile connection between the two facsimile machines.
Preferred embodiments of the invention are implemented as a computer program product having a computer usable medium with computer readable program code thereon. The computer readable code may be read and utilized by a computer system in accordance with conventional processes.